The present inventions relate generally to locating mobile receivers, and more particularly to time-synchronizing network base stations and satellite positioning system enabled mobile receivers, for example GPS enabled cellular handsets in cellular communications networks.
Satellite positioning system enabled mobile receivers are known generally, and include for example navigational and two-way radio communication devices.
Known satellite positioning systems include the Navigation System with Time and Range (NAVSTAR) Global Positioning System (GPS) in the United States of America, the Global Navigation Satellite System (GLONASS) in Russia, and the proposed European satellite navigation system (Galileo).
Regulatory and market driven forces are motivating communications equipment manufacturers and service providers to more quickly and accurately locate these and other mobile receivers, for example, to support enhanced emergency 911 (E-911) services, to provide promotional and fee based value-added services, for navigation, etc.
In the near term, network-assisted satellite based positioning schemes will likely support some of the demand for mobile receiver location services, especially for cellular handsets in cellular communication networks. The positioning of mobile receivers may also be made autonomously, in other words without network assistance.